Assembling Cell-Seeded 2d Meshes Filled With Magnetic Fibres Into 3d Intact Scaffolds With Uniform Cell Distribution By An External Magnetic Force And Endogenous Extracellular Matrix

The construction of 3-dimensional (3D) scaffolds with spatially distributed cells throughout remains a challenge despite their high demand for use in tissue and organ repair/regeneration. To tackle this challenge, here we demonstrate a new strategy for building such scaffolds. First, osteoblast-seeded magnetic meshes (consisted of interconnected electrospun magnetic nanoparticles/polycaprolactone composite fibres) were vertically aligned and tightly stacked by a magnetic force. Then, the resultant cell-seeded scaffolds were cultured in medium to facilitate the proliferation of osteoblasts as well as the secretion of extracellular matrix (ECM) by the cells. The type I collagen, main components of secreted ECM, further deposited and filled the interface between the adjacent layers of the meshes, resulting in increased binding between the mesh layers and subsequent successful construction of the 3D scaffold/cell complex with spatially distributed cells throughout the scaffold. Our strategy may pave an all new way to the development of artificial tissues that may take important parts in tissue regeneration and drug testing.